Diamyd Medical is to stop the U.S. Phase III trial evaluating its antigen-based therapy Diamyd® in type 1 diabetes patients. The decision was made after a review of efficacy data from the DiaPrevent study and a parallel European Phase III trial showed the treatment was unlikely to be effective.
Negative data from the European Phase III study were reported in May and showed Diamyd therapy did not meet the primary endpoint of preserving beta cell function at 15 months. The U.S. DiaPrevent had enrolled over 320 patients diagnosed with type 1 diabetes no more than three months prior.
Diamyd is undergoing a separate Phase II trial in type 1 diabetes that is being conducted by the Type 1 Diabetes TrialNet. Data from this study is due for presentation at the ADA meeting in San Diego next week. The potential for Diamyd to prevent type 1 diabetes in high risk children is in addition being evaluated in an externally funded and researcher-initiated Phase II study.
“We remain hopeful that Diamyd and the active substance GAD65 can be effective if administered earlier in the disease process to prevent type 1 diabetes, in certain subgroups, in combination with other drugs or in a different treatment regimen,” comments Peter Zerhouni, acting president and CEO at Diamyd Medical. “Immunological data collected in our European Phase III study has yet to be reviewed and will guide us in setting the future plan for Diamyd and GAD65.”
The Diamyd portfolio is based on the 65 kDa isoform of the recombinant human glutamic acid decarboxylase protein (rhGAD65), a major autoantigen in autoimmune diabetes, Diamyd Medical states. Diamyd therapy is designed to induce immunotolerization in patients with autoimmune diabetes to slow or prevent the destruction of pancreatic beta cells and maintain endogenous secretion of insulin.
The treatment is in addition undergoing Phase II development in patients with latent autoimmune diabetes in adults (LADA), using a different formulation of Diamyd to that used for the type 1 diabetes indication. Neurologix has licensed GAD from Diamyd Medical on a nonexclusive basis for the development of new therapies for Parkinson disease.
Diamyd Medical is developing a second, pain product based on the Nerve Targeting Drug Delivery System (NTDDS) platform it acquired through the takeover of Nurel Therapeutics in 2005. In January the firm initiated a Phase II study with lead NTDDS candidate, NP2 Enkephalin, in patients with severe cancer pain. The candidate has been developed to deliver the natural opioid enkephalin directly to the nervous system.
Two other NTDDS products are also in preclinical development. NG2 GAD uses the NTDDS platform to deliver GAD locally to nerve cells and is primarily in development for the treatment of diabetes pain, supported by grant funding from the U.S. Department of Veterans Affairs. Clinical studies of diabetes pain are planned in 2011.
Diamyd Medical says preclinical data suggests NG2 GAD could also have utility in the treatment of chronic neuropathic pain resulting from nerve damage such as spinal cord injury. The second preclinical-stage NTDDS candidate, NE2 Endomorphin, is in development for the treatment of neuropathic pain.